I. Field of the Invention
The present invention relates generally to broadcasting systems, and more particularly to a system in which supplemental data is inserted in a broadcast carrier for transmission to specially adapted receivers capable of decoding the data.
II. Discussion of the Known Art
Listeners of all kinds of music frequently wish they can remember the name, artist or other pertinent information relating to a musical piece or selection they heard during a recent broadcast. If the listener happens to hear an announcer identify the piece before or after it is played over the broadcast station, he or she may note the information down with pencil and paper if convenient. Usually, however, the selection is first heard by the listener while driving or under some other condition where it is not possible or practical to jot down identifying information so as to enable the selection to be later purchased at a record/tape store.
Broadcast stations often transmit a number of musical pieces, one right after the other, by various artists and selected from different records or tapes, without any narration or other means of identifying the title of each piece just before or after it is played. Thus, when the announcer identifies each of, e.g., five selections that were played successively over the past 15 minutes, the listener cannot be sure which title and name identifies a particular selection he or she may have especially liked.
As far as is known, no existing or proposed commercial broadcasting system affords the listener an opportunity to identify, by means of supplemental information encoded in the broadcast carrier signal, items such as the artist and title of a musical selection simultaneously with its broadcast. A frequency-modulation (FM) broadcasting system has been proposed in which auxiliary tuning and program information is inserted into a monophonic or stereophonic FM broadcast in the commercial FM band of 88 to 108 MHz. See Specifications of the Radio Data System RDS for VHF/FM Sound Broadcasting, European Broadcasting Union, Tech. 3244-E (March 1984), referred to hereafter as "the EBU system".
In the EBU system, blocks of character data are continuously inserted, in synchronized fashion, in a 57 KHz sub-carrier of a FM broadcast signal. The blocks of data may correspond to (1) the country from which the broadcast originates, (2) the area of coverage, viz., international, national or regional, and (3) the type of program such as traffic information, sports, pop music or the like. Circuitry within specially designed automobile receivers would, upon decoding the data blocks, cause the receiver either to stay tuned to the received station, or to scan for another station that is transmitting a certain kind of program information pre-selected by the driver. The EBU system does contemplate transmissions of text material (Radiotext) addressed primarily to new home receivers. It is acknowledged that a changing message display on an automobile receiver could divert the driver's attention from the road and thus present a safety hazard.
U.S. Pat. No. 4,805,217 issued Feb. 14, 1989, discloses a receiving set with a playback function. A portion of an audio signal that is reproduced by a receiver can be stored in a digital memory, for later recall by the listener. Likewise, U.S. Pat. No. 4,268,724 issued May 19, 1981, and U.S. Pat. No. 4,488,273 issued Dec. 11, 1984, disclose systems in which a received radio broadcast program is first recorded on a continuous loop of magnetic tape prior to being audibly reproduced.